Lucene example source code file (SearchTravRetLoadFieldSelectorTask.java)

This example Lucene source code file (SearchTravRetLoadFieldSelectorTask.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lucene tags/keywords

document, fieldselector, hashset, io, ioexception, override, override, searchtravretloadfieldselectortask, searchtravretloadfieldselectortask, set, setbasedfieldselector, setbasedfieldselector, string, stringtokenizer, stringtokenizer, util

The Lucene SearchTravRetLoadFieldSelectorTask.java source code

package org.apache.lucene.benchmark.byTask.tasks;
/**
 * Copyright 2005 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


import org.apache.lucene.benchmark.byTask.PerfRunData;
import org.apache.lucene.document.FieldSelector;
import org.apache.lucene.document.SetBasedFieldSelector;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexReader;

import java.util.StringTokenizer;
import java.util.Set;
import java.util.HashSet;
import java.util.Collections;
import java.io.IOException;

/**
 * Search and Traverse and Retrieve docs task using a SetBasedFieldSelector.
 *
 * <p>Note: This task reuses the reader if it is already open.
 * Otherwise a reader is opened at start and closed at the end.
 *
 * <p>Takes optional param: comma separated list of Fields to load.

 * 
 * <p>Other side effects: counts additional 1 (record) for each traversed hit, 
 * and 1 more for each retrieved (non null) document.</p>
 */
public class SearchTravRetLoadFieldSelectorTask extends SearchTravTask {

  protected FieldSelector fieldSelector;
  public SearchTravRetLoadFieldSelectorTask(PerfRunData runData) {
    super(runData);
    
  }

  @Override
  public boolean withRetrieve() {
    return true;
  }


  @Override
  protected Document retrieveDoc(IndexReader ir, int id) throws IOException {
    return ir.document(id, fieldSelector);
  }

  @Override
  public void setParams(String params) {
    this.params = params; // cannot just call super.setParams(), b/c it's params differ.
    Set<String> fieldsToLoad = new HashSet();
    for (StringTokenizer tokenizer = new StringTokenizer(params, ","); tokenizer.hasMoreTokens();) {
      String s = tokenizer.nextToken();
      fieldsToLoad.add(s);
    }
    fieldSelector = new SetBasedFieldSelector(fieldsToLoad, Collections.<String> emptySet());
  }


  /* (non-Javadoc)
  * @see org.apache.lucene.benchmark.byTask.tasks.PerfTask#supportsParams()
  */
  @Override
  public boolean supportsParams() {
    return true;
  }
}